G'day Everybody.
Well I finally finished building a new quad and put APM 2.0 on it, have to say I was very impressed, no PID changes needed, and very solid Alt hold. Did several test flights, everything on the board seemed to be functioning ok until I fitted an Attopilot current sensor to the board, after which I ended up with magic smoke from under the GPS sheild :( I have since found out that the sensor I attached is dodgy and supplied full battery voltage to the boards input. After close inspection of the board, after removing the sheild I can see one chip visibly burnt. It is marked with the leters JBR See photo:
So, what chip is this? is it easily available? and what are the chances of recovering this board?
When powered by USB all LEDs will light up, but the board is not recognised via USB
The other problem I have spotted on the board is another small chip marked G33 128 just next to the UART2 pads (this is probably not relevant now given the damage to the board)but it seems to have been misaligned on the board during assembly
So have I turned it into a desk ornament? or is it recoverable?
Chers Paul
Replies
I'm using the AttoPilot 90A unit. I plugged it in before reading your post. Luckily my board didn't take a smoke break :)
Anyway I'm using APM Planner 1.1.23 and have installed the latest quadcopter firmware on the new APM2 board. It's not on a copter yet because I'm waiting for a replacement transmitter but I've started setting it up to put on a quad and put the battery monitor to test it out.
It doesn't seem though that the code supports it because I get a NOT AVAILALBLE dialog when I try to choose that as my sensor. Actually I get it no matter what sensor I choose. If I try to put in APM Input voltage, it doesn't let me either.
Is voltage and current sensing working in the current multicopter code or is it a problem with new APM board?
BTW, I see it reading values in the other fields so it seems to be working except for the above problems. With a 3s BATTERY I'm getting these values:
2 - Measured battery voltage 11.805
3 - Battery Voltage Calced 11.409
4 - Voltage Divider Calced 15.70
5 - Amperese per volt 54.64
I didn't find anything in the wiki about it.
Is there a voltage divider on the ADC pins on APM2? I couldn't see one on the Eagle files....
Keen to avoid the same mistake, as I'm setting up my APM2. For now, I'm tempted to feed in the voltage and current readings as scaled by the Attopilot, albeit to just 3.3volts, its better than blowing things up!
Hope you get your board sorted.
Rick
If i didn't make mistakes reading schemas the upper photo fried component is TS5A23157 which is "dual single-pole double-throw (SPDT) analog switch"
http://www.ti.com/lit/ds/scds165d/scds165d.pdf
And component in the lower photo is MIC5219 which seems to be Voltage regulator
http://www.micrel.com/_PDF/mic5219.pdf
Maybe Jordi or other developer can confirm this and give info what you can do with the board. Hope you will get it fixed.